st: Issue re. heckprob

Hello,
I am investigating the transitions to parenthood after age 30 for
those in the survey who are childless at age 30.
I would like to take into account for the selection of couples who are
still childless at age 30, by applying a heckprob model.
Since I want to estimate time to entry into parenthood, I have a
probit model as a selection model (first-step equation) and a discrete
time survival model for the latter binary variable as a behavioural
equation (second step).
Can the Heckprob command deal with this - or is it set up for a
dataset that has only one line per person i.e. that is wide? If so,
can we do the Heckprob physically in two parts - i.e. get the inverse
mills ratio from the selection model and then put this into a discrete
time probit model?
Thanks.
Best,
Eleonora
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